Polishing composition and polishing method

ABSTRACT

A polishing composition contains alumina, a complexing agent, and an oxidizing agent. It is preferable that the complexing agent is at least one compound selected from an α-amino acid, ammonia, and an ammonium salt. The polishing composition is preferably used in applications for polishing an object having a resin section with a trench, and a conductor layer provided on the resin section so that at least the trench is filled with the conductor layer.

RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.11/083,565, filed Mar. 18, 2005, entitled POLISHING COMPOSITION ANDPOLISHING METHOD, which claims priority to Japanese Patent ApplicationNo. 2004-081585, filed Mar. 19, 2004, both of which are incorporatedherein by reference.

BACKGROUND OF THE INVENTION

The present invention relates to a polishing composition used, forexample, in polishing for forming conductor wiring for a circuit board,and to a polishing method using such a polishing composition.

In recent years, it has been required that circuit boards such assemiconductor package substrates in which ICs, transistors, and the likeare mounted, have various functions and high-performance in connectionwith the acceleration and high integration of LSIs. A damascene processwherein a chemical mechanical polishing (CMP) technology is used hasbecome the main method for forming conductor wiring for a circuit board.In the case of formation of conductor wiring, first, on a resin sectionwhich has trenches, a conductor layer is formed so that at least thetrenches is filled with the conductor layer. Then, at least a portion ofthe conductor layer positioned outside the trenches is removed bypolishing so that a portion of the resin section between adjacenttrenches is exposed. In this way, at least a part of the portion of theconductor layer positioned inside the trenches remains on the resinsection, and the portion of the conductor layer which remains functionsas conductor wiring.

A polishing composition disclosed in Japanese Laid-Open PatentPublication No. 2003-257910 is used in polishing for forming conductorwiring. The polishing composition contains abrasive, a copper chelatingagent, a copper etching agent, and an oxidizing agent.

In order to enhance the efficiency of polishing for forming conductorwiring, it is important not only to raise the polishing quantity of aconductor layer per unit time (polishing rate of a conductor layer), butalso to raise the polishing quantity of a resin section per unit time(polishing rate of a resin section). Nevertheless, the polishingcomposition described in Japanese Laid-Open Patent Publication No.2003-257910 can polish a conductor layer in a high stock removal rate,but cannot polish a resin section in a high stock removal rate.Therefore, although the polishing rate of a conductor layer increaseswhen the polishing composition is used in polishing for formingconductor wiring, the polishing rate of a resin section seldom improves.

SUMMARY OF THE INVENTION

Accordingly, an object of the present invention is to provide apolishing composition which can raise the polishing rate of a conductorlayer, and the polishing rate of a resin section.

To achieve the foregoing and other objectives and in accordance with thepurpose of the present invention, a polishing composition is provided.The polishing composition includes alumina, a complexing agent, and anoxidizing agent. The polishing composition is used in an application forpolishing an object having a resin section with a trench, and aconductor layer provided on the resin section so that at least thetrench is filled with the conductor layer,

The present invention also provides a polishing method. The methodincludes preparing the above polishing composition and polishing anobject having a resin section with a trench, and a conductor layerprovided on the resin section so that at least the trench is filled withthe conductor layer, by using the prepared polishing composition.

Other aspects and advantages of the invention will become apparent fromthe following description, taken in conjunction with the accompanyingdrawings, illustrating by way of example the principles of theinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention, together with objects and advantages thereof, may best beunderstood by reference to the following description of the presentlypreferred embodiments together with the accompanying drawings in which:

FIGS. 1 and 2 are sectional views of an object to be polished forexplaining a polishing method according to one embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

An embodiment of the present invention will now be described withreference to FIGS. 1 and 2.

First of all, a method for forming conductor wiring 14 (refer to FIG. 2)for a wiring board will be explained.

In forming the conductor wiring 14, as shown in FIG. 1, a conductorlayer 13 is formed first on an insulating resin layer 11 (resin section)which is provided on a substrate 10 and has trenches 12. The substrate10 consists of, for example, ceramics or metal. The resin layer 11 maybe formed with any of a glass epoxy resin, a polyimide resin, a paperepoxy resin, and a Bakelite resin. The trenches 12 are formed so as tohave a predetermined designed pattern, for example, by well-knownlithography technology and pattern-etching technology. The conductorlayer 13 is formed on the resin layer 11 so as to fill at least thetrenches 12. The conductor layer 13 is formed, for example, by PVD, CVD,or plating, and consists of copper containing material such as copper, acopper-aluminum alloy, and a copper-titanium alloy.

Subsequently, at least a portion of the conductor layer 13 positionedoutside the trenches 12 is removed by polishing so that the resin layer11 is exposed. Thereby, at least a part of the portion of the conductorlayer 13 positioned inside the trenches 12 remains on the resin section11, and the portion of the conductor layer 13 which remains functions asconductor wiring 14. As shown in FIG. 2, after polishing, top faces ofthe conductor wiring 14 and resin layer 11 are exposed. The exposed topfaces of the conductor wiring 14 and the resin layer 11 are mutuallyflush, and both are smooth. Polishing for forming the conductor wiring14 is performed by one time of polishing step. A polishing compositionaccording to this embodiment contains alumina, a complexing agent, anoxidizing agent, and water, and is used in polishing for forming theconductor wiring 14.

Alumina in the polishing composition has a function of mechanicallypolishing an object to be polished. Alumina to be contained in thepolishing composition may be produced by grinding and classificationafter heat-treating aluminum hydroxide, or it may be colloidal aluminaor fumed alumina. The polishing composition may also contain two typesof different alumina.

From the viewpoint of improvement in polishing rates of the conductorlayer 13 and resin layer 11, the content of alumina in the polishingcomposition is preferably 0.1 mass % or more, more preferably 1 mass %or more, further preferably 5 mass % or more, and most preferably 7 mass% or more. On the other hand, from the viewpoint of the improvement ofdispersibility and solubility of each component in the polishingcomposition, the content of alumina is preferably 50 mass % or less,more preferably 30 mass % or less, and most preferably 20 mass % orless.

When the alumina contained in the polishing composition is alumina otherthan fumed alumina and colloidal alumina, from the viewpoint ofimprovement in the polishing rate of the resin layer 11, the averageparticle diameter of the alumina measured by an electric resistancemethod (a Coulter method) is preferably 0.1 μm or more, and furtherpreferably 1 μm or more. On the other hand, from the viewpoint ofsuppressing scratches (linear flaws) occurring while polishing, theaverage particle diameter of the alumina measured by the electricresistance method is preferably 50 μm or less, and more preferably 10 μmor less.

When the alumina contained in the polishing composition is fumed aluminaor colloidal alumina, from the viewpoint of improvement in the polishingrate of the resin layer 11, the average particle diameter of the aluminameasured by a laser diffraction method is preferably 0.1 μm or more. Onthe other hand, from the viewpoint of suppressing scratches occurringwhile polishing, the average particle diameter of the alumina measuredby the laser diffraction method is preferably 10 μm or less, and furtherpreferably 1 μm or less.

A completing agent in the polishing composition has the function ofcatching metal generated in the polishing composition by the polishingof the conductor layer 13 and enhancing the polishing of the conductorlayer 13. A completing agent to be contained in the polishingcomposition may be at least one compound selected from organic acidssuch as oxalic acid, citric acid, succinic acid, maleic acid, andtartaric acid; α-amino acids such as glycine and alanine; multiplevalued amine such as ethylenediamine and triethylenetetramine; ammonia;and an ammonium salt. Although a preferable complexing agent changes bya type of material constituting the conductor layer 13, an α-amino acid,ammonia, or an ammonium salt is preferable since having a strong actionof enhancing copper polishing when the conductor layer 13 consists ofcopper.

When only at least one compound selected from between ammonia and anammonium salt is contained as a complexing agent in the polishingcomposition, there is a possibility that corrosion may arise on thesurface of the conductor layer 13 depending on the content of acomplexing agent. Moreover, when only an α-amino acid is contained as acomplexing agent in the polishing composition, the polishing rate ofcopper does not become high depending on the content of the complexingagent in comparison with the case that only at least one compoundselected from between the ammonia and ammonium salt is contained as acompleting agent in the polishing composition. Therefore, in order tomake the suppression of corrosion of the conductor layer 13 and theimprovement in the polishing rate of copper compatible, it is preferablethat at least one compound, selected from between the ammonia andammonium salt, and the α-amino acid are contained as the completingagent in the polishing composition.

What are cited as specific examples of the α-amino acids are neutralamino acids such as glycine, alanine, valine, leucine, isoleucine,alloisoleucine, serine, threonine, allothreonine, cysteine, methionine,phenylalanine, tryptophan, thyrosin, proline, and cystine; acidic aminoacids such as glutamic acid and aspartic acid; and basic amino acidssuch as arginine and histidine. At least one compound is used amongthese. Especially, since procurement is easy and moreover the polishingrate of the conductor layer 13 is improved well, glycine and α-alanineacid are preferable, and glycine is more preferable. The α-amino acidmay be any of an L-enantiomer and a D-enantiomer. When the conductorlayer 13 consists of copper, from the viewpoint of improvement in thepolishing rate of copper, the content of the α-amino acid in thepolishing composition is preferably 0.01 mass % or more, and morepreferably 0.1 mass % or more. On the other hand, from the viewpoint ofcost effectiveness, the content of the α-amino acid is preferably 20mass % or less, and is more preferably 10 mass % or less.

What are cited as specific examples of the ammonium salts are ammoniumsalts of inorganic acids such as ammonium carbonate, ammoniumhydrogencarbonate, ammonium phosphate, ammonium nitrate, ammoniumsulfate, and ammonium chloride; and ammonium salts of organic acids suchas ammonium oxalate, ammonium citrate, succinic acid ammonium, andammonium tartrate. At least one compound is used among these. Sinceammonia has an action of polishing an object chemically and does notcontain metal impurities, ammonia is preferable to be contained in thepolishing composition as the complexing agent. When the conductor layer13 consists of copper, from the viewpoint of improvement in thepolishing rate of copper, sum of the content of the ammonia and ammoniumsalts in the polishing composition is preferably 0.1 mass % or more, andmore preferably 1 mass % or more. On the other hand, from the viewpointof suppressing corrosion of the conductor layer 13, the content ispreferably 10 mass % or less, and more preferably 5 mass % or less.

An oxidizing agent in the polishing composition makes the operation ofenhancing the polishing of the conductor layer 13 by chemical polishing.An oxidizing agent to be contained in the polishing composition may beat least one compound selected from persulfuric acid, periodic acid,perchloric acid, peracetic acid, performic acid, nitric acid and a saltthereof, and hydrogen peroxide. Among them, hydrogen peroxide ispreferable because hydrogen peroxide little contaminated with metalimpurities is inexpensively and easily available.

From the viewpoint of improvement in the polishing rate of the conductorlayer 13, the content of the oxidizing agent in the polishingcomposition is preferably 0.01 mass % or more, more preferably 0.1 mass% or more, and further preferably 0.3 mass % or more. On the other hand,from the viewpoint of cost effectiveness, the content of the oxidizingagent is preferably 10 mass % or less, more preferably 6 mass % or less,and further preferably 3 mass % or less.

Water in the polishing composition acts as a medium for dispersing ordissolving components in the polishing composition. Water to becontained in the polishing composition preferably contains as littleimpurity as possible so as not to hinder the actions of each componentin the polishing composition, and preferably is deionized water, ultrapure water, or distilled water.

From the viewpoint of improvement in the polishing rate of copper, thepH of the polishing composition is preferably 7 or more, more preferably8.5 or more, and further preferably 9 or more. On the other hand, fromthe viewpoint of suppressing the corrosion of the conductor layer 13,the pH is preferably less than 12, more preferably less than 11.5, andfurther preferably less than 11. In addition, when the polishingcomposition contains at least one compound, selected from ammonia andammonium salt, and an α-amino acid as the complexing agent, it ispreferable to set the content of the complexing agent in considerationof the above-mentioned range of the pH.

In order to suppress the aggregation of alumina in the polishingcomposition and to enhance redispersibility, alumina sol may be added tothe polishing composition according to this embodiment, as anaggregation restrainer. When alumina sol is added to the polishingcomposition, it is possible to suppress the generation of hard caking,which becomes a cause of lowering the redispersibility of alumina, andthe aggregation of alumina, which causes scratches generated on thepolished object, because of an action of alumina sol dispersedcolloidally in the polishing composition. It is possible to obtainalumina sol by dispersing hydrated alumina, such as boehmite,pseudo-boehmite, diaspore, gibbsite, and bayerite, or aluminum hydroxidecolloidally in an aqueous acid. Especially, alumina sol obtained bydispersing boehmite or pseudo-boehmite in the aqueous acid ispreferable. From the viewpoint of suppressing the aggregation ofalumina, the content of alumina sol in the polishing composition ispreferably 0.05 mass % or more, or preferably 0.1 mass % or more, andfurther preferably 0.5 mass % or more. On the other hand, from theviewpoint of the improvement of dispersibility and solubility of eachcomponent in the polishing composition, the content of alumina sol ispreferably 5 mass % or less, more preferably 3 mass % or less, andfurther preferably 2 mass % or less.

When polishing for forming the conductor wiring 14 using the polishingcomposition according to this embodiment is performed, the conductorlayer 13 and resin layer 11 are mechanically polished by action ofalumina in the polishing composition at a high stock removal rate.Especially, since being enhanced by action of the complexing agent thatcatches metal generated in the polishing composition by the polishing ofthe conductor layer 13, and action of the oxidizing agent that haschemical polishing, the polishing of the conductor layer 13 is performedat an especially high stock removal rate. Therefore, according to thepolishing composition, it is possible to raise the polishing rate of theconductor layer 13 and the polishing rate of the resin layer 11, and theefficiency of the polishing for forming the conductor wiring 14improves.

It should be apparent to those skilled in the art that the presentinvention may be embodied in many other specific forms without departingfrom the spirit or scope of the invention. Particularly, it should beunderstood that the invention may be embodied in the following forms.

The polishing composition may be prepared by diluting a stock solutionwith water at the time of use. The stock solution is easy in storage andtransportation.

The polishing composition may be stored in the state where an oxidizingagent is separated from the other components. In this case, thepolishing composition is provided for use after the oxidizing agent hasbeen mixed with the other components. According to this, the oxidizingagent is prevented from decomposing in the polishing composition duringstorage.

Into the polishing composition, a well-known additive such as asurfactant, a thickener, an emulsifier, a antirust agent, apreservative, an antifungal agent, an antifoaming agent, and a pHadjuster may be added.

The conductor layer 13 may be provided on a resin substrate (resinsection) instead of being provided on the resin layer 11 provided on thesubstrate 10.

In the next place, Examples and Comparative Examples according to thepresent invention will be described.

Each of an abrasive, a complexing agent, an oxidizing agent, and aluminasol was mixed to water as required in order to prepare polishingcompositions according to Examples 1 to 22 and Comparative Examples 1 to8. The detail of the abrasive, complexing agent, oxidizing agent, andalumina sol in each polishing composition is as being shown in Table 1.In conjunction with this, measurements of pH of respective polishingcompositions are shown in Table 1. Here, the unit of a value whichindicates the content of each component in Table 1, is mass %.

TABLE 1 First Second complexing complexing Alumina Abrasive agent agentOxidizing agent sol Kind Content Kind Content Kind Content Kind ContentContent pH Ex. 1 A3 20 G 0.2 NH₃ 2 H₂O₂ 1 1.5 10.1 Ex. 2 A3 15 G 0.2 NH₃2 H₂O₂ 1 1.5 10.1 Ex. 3 A3 7 G 0.2 NH₃ 2 H₂O₂ 1 1.5 10.1 Ex. 4 A1 15 G0.2 NH₃ 2 H₂O₂ 1 1.5 10.1 Ex. 5 A2 15 G 0.2 NH₃ 2 H₂O₂ 1 1.5 10.1 Ex. 6CA 15 G 0.2 NH₃ 2 H₂O₂ 1 1.5 10.1 Ex. 7 FA 15 G 0.2 NH₃ 2 H₂O₂ 1 1.510.1 Ex. 8 A3 15 G 0.01 NH₃ 2 H₂O₂ 1 1.5 10.1 Ex. 9 A3 15 G 3 NH₃ 2 H₂O₂1 1.5 10.1 Ex. 10 A3 15 — NH₃ 2 H₂O₂ 1 1.5 10.1 Ex. 11 A3 15 A 0.2 NH₃ 2H₂O₂ 1 1.5 10.1 Ex. 12 A3 15 G 0.2 NH₃ 0.1 H₂O₂ 1 1.5 9.2 Ex. 13 A3 15 G0.2 NH₃ 5 H₂O₂ 1 1.5 10.9 Ex. 14 A3 15 G 0.2 — H₂O₂ 1 1.5 7.3 Ex. 15 A315 G 0.2 NH₃ 2 H₂O₂ 0.1 1.5 10.1 Ex. 16 A3 15 G 0.2 NH₃ 2 H₂O₂ 0.2 1.510.1 Ex. 17 A3 15 G 0.2 NH₃ 2 H₂O₂ 0.5 1.5 10.1 Ex. 18 A3 15 G 0.2 NH₃ 2H₂O₂ 5 1.5 10.1 Ex. 19 A3 15 G 0.2 NH₃ 2 APS 1 1.5 10.1 Ex. 20 A3 15 G0.2 NH₃ 2 H₂O₂ 1 — 10.1 Ex. 21 A3 15 G 0.2 NH₃ 2 H₂O₂ 1 0.015 10.1 Ex.22 A3 15 G 0.2 NH₃ 2 H₂O₂ 1 0.15 10.1 C. Ex. 1 A3 0.5 G 0.2 NH₃ 2 H₂O₂ 11.5 10.1 C. Ex. 2 A3 3 G 0.2 NH₃ 2 H₂O₂ 1 1.5 10.1 C. Ex. 3 — G 0.2 NH₃2 H₂O₂ 1 1.5 10.1 C. Ex. 4 CS 15 G 0.2 NH₃ 2 H₂O₂ 1 1.5 10.1 C. Ex. 5 FS15 G 0.2 NH₃ 2 H₂O₂ 1 1.5 10.1 C. Ex. 6 A3 15 — — H₂O₂ 1 1.5 7.3 C. Ex.7 A3 15 — — — 1.5 7.3 C. Ex. 8 A3 15 G 0.2 NH₃ 2 — 1.5 10.1

In the column entitled “Abrasive” of Table 1,

“A1” denotes alumina with the average particle diameter of 1.3 μm,

“A2” denotes alumina with the average particle diameter of 3.0 μm,

“A3” denotes alumina with the average particle diameter of 5.5 μm,

“CA” denotes colloidal alumina with the average particle diameter of0.05 μm,

“FA” denotes fumed alumina with the average particle diameter of 0.2 μm,

“CS” denotes colloidal silica with the average particle diameter of 0.07μm, and

“FS” denotes fumed silica with the average particle diameter of 0.2 μm.

The average particle diameter of alumina was measured by the electricresistance method using “Coulter Multisizer” made by Beckman CoulterInc., and the average particle diameters of colloidal alumina, fumedalumina, colloidal silica, and fumed silica were measured by the laserdiffraction method using “N4 Plus Submicron Particle Sizer” made byBeckman Coulter Inc.

In the columns entitled “First complexing agent” and “Second complexingagent” of Table 1,

“G” denotes glycine,

“A” denotes alanine, and

“NH₃” denotes ammonia.

In the column entitled “Oxidizing agent” of Table 1,

“H₂O₂” denotes hydrogen peroxide, and

“APS” denotes ammonium sulfite.

A copper blanket-wafer and an epoxy resin blanket-wafers were polishedfor 1 minute under the following polishing conditions using respectivepolishing compositions according to Examples 1 to 22 and ComparativeExamples 1 to 8. Then, the polishing rate of copper and the polishingrate of epoxy resin were found on the basis of the following formulae.The results are shown in the column entitled “Polishing rate” of Table2. In addition, each copper blanket-wafer has a copper film formed on an8-inch silicon wafer with an electroplating method, and each epoxy resinblanket-wafer has a film consisting of an epoxy resin (ABF by AjinomotoCo., Inc.) on an 8-inch silicon wafer with spin coating.

<Polishing Conditions>

Polishing apparatus: single-sided CMP polishing machine, “ARW” made byMAT Corporation,

Polishing pad: multilayered polishing pad “IC-1000/Suba400” made ofpolyurethane and made by Rodel Corporation,

Polishing pressure: 28 kPa (about 6 psi),

Rotational frequency of press platen: 90 min⁻¹,

Feed rate of polishing composition: 140 mL/min,

Rotational frequency of carrier for supporting wafer: 95 min⁻¹

<Formula of Polishing Rate of Copper>

Polishing rate of copper [μm/min]=(thickness of copper blanket-waferbefore polishing [μm]−thickness of copper blanket-wafer after polishing[μm])/polishing time [min].

In addition, the thickness of the copper blanket-wafers before and afterpolishing was measured using a sheet resistance measuring instrument,“VR-120” made by Kokusai Electric system service Co., Ltd.

<Formula of Polishing Rate of Epoxy Resin>

Polishing rate of epoxy resin [μm/min]=(weight of epoxy resinblanket-wafer before polishing [g]−weight of epoxy resin blanket-waferafter polishing [g])/specific gravity of epoxy resin [g/cm³]/polishingarea of epoxy resin blanket-wafer [cm²]/polishing time [min]

Patterned wafers which each had a copper conductor layer on a resinlayer which was made of an epoxy resin and had trenches were prepared.The trenches include a trench with the depth of 20 μm and the width of85 μm, a trench with the depth of 20 μm and the width of 300 μm, and atrench with the depth of 20 μm and the width of 500 μm. The patternedwafers were polished under the above-mentioned polishing conditionsuntil a top face of a portion of each resin layer between adjacenttrenches was exposed using each of the polishing compositions accordingto Examples 1 to 22 and Comparative Examples 1 to 8. The time taken forthe top face of the portion of each resin layer to be exposed is shownin the column entitled “Removing time” of Table 2.

Dishing depth was measured in a region (W85), in which a trench with thewidth of 85 μm is formed, a region (W300), in which a trench with thewidth of 300 μm is formed, and a region (W500), in which a trench withthe width of 500 μm is formed, in each of the patterned wafers afterpolished using each polishing composition according to Examples 1 to 22and Comparative Examples 1 to 8. The results are shown in the columnentitled “Dishing depth” of Table 2. The measurement of the dishingdepth was performed using a profiler “HRP340” which is a contact typesurface measurement apparatus made by KLA-Tencor Corporation. Inaddition, that the plus value of the dishing depth means that theportion of the conductor layer positioned inside the trench isdepressed, and the minus value of the dishing depth means that theportion of the conductor layer positioned inside the trench protrudes.

The redispersibility of abrasives was evaluated as follows using each ofthe polishing compositions according to Examples 1 to 22 and ComparativeExamples 1 to 8 which were charged in vessels made of polypropylene, andwhich were left as it is for ten days. Thus, they were evaluated to beexcellent (E) when there was no precipitate or when precipitatesdisappeared by shaking within 1 minute even if the precipitates were ineach polishing composition after having been left as it is for ten days,to be good (G) when the precipitates disappeared by shaking for 1 to 10minutes, and to be defective (D) when the precipitates did not disappeareven by shaking for 10 minutes or more. The results are shown in thecolumn entitled “Redispersibility” of Table 2

TABLE 2 Polishing rate [μm/min] Removing time Dishing depth [μm] CopperEpoxy resin [sec] W300 W500 W85 Redispersibility Ex. 1 5.2 6.7 150 −0.5−0.7 −0.7 E Ex. 2 7.1 6.2 120 0.4 −0.3 −0.3 E Ex. 3 5.2 2.1 150 1.5 1.81.3 E Ex. 4 5.1 3.7 150 0.3 0.3 0.3 E Ex. 5 6.2 5 150 0.8 1.0 1.1 E Ex.6 6.5 4.5 150 1.0 0.8 0.8 E Ex. 7 6.7 5 150 1.2 1.0 0.9 E Ex. 8 5.0 6.2150 −0.5 −0.5 −0.3 E Ex. 9 7.6 6.2 120 0.5 0.4 0.3 E Ex. 10 5.2 6.2 150−0.6 −0.4 −0.5 E Ex. 11 5.3 5.9 150 −0.7 −0.6 −0.6 E Ex. 12 4.2 6.2 180−1.0 −0.8 −1.0 E Ex. 13 6.6 6.2 150 0.5 0.3 0.3 E Ex. 14 4.1 6.2 180−0.9 −0.9 −1.1 E Ex. 15 3.1 6.2 180 −1.5 −1.7 −1.5 E Ex. 16 4.2 6.2 180−1.1 −0.8 −0.7 E Ex. 17 5.4 6.2 150 −0.8 −0.8 −0.9 E Ex. 18 5.3 6.2 150−0.3 −0.6 −0.6 E Ex. 19 3.1 6.2 180 −1.6 −2.0 −1.5 E Ex. 20 6.9 5.9 1200.5 −0.3 −0.3 D Ex. 21 7.1 6.2 120 0.4 −0.3 −0.3 G Ex. 22 7.1 6.2 1200.4 −0.3 −0.3 G C. Ex. 1 4.8 0 150 4.7 4.4 4.8 E C. Ex. 2 5.0 0 150 5.14.6 4.5 E C. Ex. 3 2.5 0 180 3.5 3.3 2.8 E C. Ex. 4 4.7 0.2 150 5.1 4.64.5 E C. Ex. 5 4.5 0.3 150 4.8 4.1 3.9 E C. Ex. 6 0.6 6.2 180 −3.3 −3.8−4.3 E C. Ex. 7 0.9 6.2 240 −3.5 −4.2 −3.8 E C. Ex. 8 1.4 6.2 150 −1.5−2 −2 EAs shown in Table 2, in Examples 1 to 22, the polishing rate of copperwas high, that is, 3.0 μm/min or more, and the polishing rate of epoxyresin was also high, that is, 2.0 μm/min or more. On the other hand, inComparative Examples 1 to 8, the polishing rate of copper was less than3.0 μm/min, or the polishing rate of epoxy resin was less than 2.0μm/min. A reason why the polishing rate is low in Comparative Examples 1and 2 is that the content of alumina in each polishing composition ofComparative Examples 1 and 2 is small. In addition, a reason why thepolishing rate is low in Comparative Examples 3 to 8 is that eachpolishing composition of Comparative Examples 3 to 8 does not contain atleast one among an abrasive, a complexing agent, and an oxidizing agent.

In order to obtain a favorable result about the removing time anddishing depth, it was found that it was preferable to set the content ofalumina at nearly 15 mass % from the results of Examples 1 to 3, to setthe content of the α-amino acid at 0.2 mass % or more from the resultsof Examples 2, 8, and 9, to set the content of ammonia at nearly 2 mass% from the results of Examples 2, 12, and 13, to use both the α-aminoacid and ammonia as complexing agents from the results of Examples 13and 14, and to set the content of hydrogen peroxide at nearly 1 mass %from the results of Examples 2, 15 to 18. From the results of Examples 2and 11, it was confirmed that copper polishing is especially enhancedwhen glycine was used as a complexing agent. From the results ofExamples 2, 20 to 22, it was confirmed that redispersibility isespecially favorable when the content of alumina sol was set at 1.5 mass% or more.

The present examples and embodiments are to be considered asillustrative and not restrictive and the invention is not to be limitedto the details given herein, but may be modified within the scope andequivalence of the appended claims.

1-20. (canceled)
 21. A polishing method comprising: preparing apolishing composition including alumina, a complexing agent, and anoxidizing agent; and polishing an object having a resin section with atrench, and a conductor layer provided on the resin section so that atleast the trench is filled with the conductor layer, by using theprepared polishing composition.
 22. The method according to claim 21,wherein the resin section is a resin layer provided on a substrate. 23.The method according to claim 21, wherein the complexing agent includesat least one compound selected from an α-amino acid, ammonia, and anammonium salt.
 24. The method according to claim 21, wherein thecomplexing agent includes an α-amino acid and at least one compoundselected from ammonia and an ammonium salt.
 25. The method according toclaim 24, wherein the complexing agent includes glycine or alanine andammonia.
 26. The method according to claim 21, the polishing compositionfurther contains alumina sol.
 27. The method according to claim 21,wherein a pH of the polishing composition is 7 or more.
 28. A polishingmethod comprising: preparing a polishing composition including alumina,an α-amino acid, ammonia or an ammonium salt, hydrogen peroxide, aluminasol, and water; and polishing an object having an insulating resinsection with a trench, and a copper conductor layer provided on theresin section so that at least the trench is filled with the conductorlayer, by using the prepared polishing composition.